竖井掘进机空气洗井流场与携渣效率的数值模拟  

Numerical simulation on the flow field and slag carrying efficiency of air flush drilling for vertical shaft boring machine

作　　者：焦宁 王衍森 孟陈祥[1] JIAO Ning;WANG Yansen;MENG Chenxiang(College of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou 221116)

机构地区：[1]中国矿业大学力学与土木工程学院,江苏徐州221116 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116

出　　处：《煤炭学报》2020年第S01期522-531,共10页Journal of China Coal Society

基　　金：国家重点研发计划资助项目(2016YFC0600903);中央高校基本科研业务费资助项目(2018ZZCX04)

摘　　要：针对现有竖井掘进机排渣方式的不足,借鉴大直径竖井钻机的流体洗井排渣方式,提出了一种适用于井筒全断面掘进的流体洗井系统。基于部分假定并结合实际工况,分析确定了流体洗井系统的基本参数和典型参数取值。主要采用FLUENT流体仿真软件,开展了空气洗井流场与排渣效率的数值模拟。首先,对空气洗井系统的基本参数进行了优化:通过单因素数值分析,以排渣管内径向、切向和竖直方向速度分量以及井底流场涡流情况等为评价指标,得到了1组在一定程度上最优的洗井系统参数;通过正交试验分析得到了排渣管内径、射流口角度等参数对井底流场的影响规律:对井底流场影响最大的为排渣管内径,影响最小的为射流口角度和刀盘与井底夹角。其次,进行了气固两相流的洗井排渣数值模拟:把岩屑假定为均匀的球体颗粒,并将其设置为离散相,以累计排出岩屑质量、排出岩屑的质量速率、清渣率和携渣率为评价指标,得到了岩屑粒径、排渣高度和入口空气流量对洗井排渣效果的影响规律:洗井排渣效果与岩屑颗粒粒径呈负相关、与入射口空气流量大致呈正相关,而排渣高度对洗井排渣效果基本没有较大的影响。最后,简要介绍了相似模型试验的验证情况,基于所推导出的相似准则,开展了相似模化设计;利用自行设计加工的模型实验台,完成了几何相似比为1∶20的模型实验。模型实验和数值模拟获得的规律基本相同,表明数值计算结果具有一定的准确性,为后续开展大尺寸模型实验或现场试验研究,提供了理论依据和基础参数。In view of the deficiency of the existing vertical shaft boring machine slag discharge mode, a fluid washing system suitable for a full-section shaft driving is proposed by referring to the fluid washing and slag discharge mode of large diameter shaft drilling rig. Based on some assumptions and combined with actual working conditions, the basic parameters and typical parameters of fluid well washing system are determined. FLUENT fluid simulation software is mainly used to carry out the numerical simulation of air well washing flow field and slag removal efficiency. First, the basic parameters of the air well cleaning system are optimized through single-factor numerical analysis, and the radial tangential and vertical velocity components and the eddy current in the bottom hole are used as the evaluation indexes to obtain a set of optimal well flushing system parameters to a certain extent. Through orthogonal test analysis, the influence law of parameters such as the inner diameter of slag discharge pipe and the angle of jet nozzle on the flow field at the bottom of the well is obtained. The inner diameter of the slag discharge pipe has the greatest influence on the flow field at the bottom of the well, while the angle of the jet nozzle and the included angle between the cutter head and the bottom of the well have the least influence. Second, the numerical simulation of gas-solid two-phase flow is carried out. The cuttings are assumed to be homogeneous spherical particles and set as discrete phase, the cumulative cuttings discharge quality and mass rate of cuttings discharge as well as slag removal rate and slag carrying rate are used as evaluation indexes, the influence law of inlet air flow at cuttings particle size and slag discharge height on the effect of well washing and slag discharge are obtained. There is a negative correlation between the effect of well flushing and debris particle size and a positive correlation between the air flow at the entrance, and the height of discharge has little effect on the ef

关 键 词：竖井掘进机 空气洗井 井底流场 携渣效率 气固两相流 

分 类 号：TU621[建筑科学—建筑技术科学]